Internal-combustion engine.



P. O. KILGORE.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED MAY 28, 1912.

1,056,690, Patented Mar. 18, 1913.

4 SHEETS-SHEET 1'.

M MEAL/L P. O. KILGORE. INTERNAL COMBUSTION ENGINE. APPLICATION FILED MAY 28. 1912,

1,056,690. Patented Mar.18,1913.

4 SHEETS'SHEET 2.

E. 0. KILGORE. INTERNAL COMBUSTION ENGINE.

APPLIOATION FILED MAY 28, 1912.

Patented Mar. 18, 1913.

4 SHEETS-SHEET s.

F. O. KILGORE.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED MAY 28, 1912, v

Patented Mar. 18, 1913.

4 SHEETS-SHEET 4.

L i I WILEY/235w:

' To all whom it may. concern:

rnnnnarcx o. KILGORE, or .SOMIERVILLE, massesHummus. T

m'rmmancomnpsrxon En ma Be it'kno'wn that I, FREDERICK O. K 1Li cons, a citizen of the United States, residing in Somerville, county of Middlesex, and- State of Massachusetts, have invented an Improvement in Internal-Combustion En-..

gines, of which the following description, in connection with the accompanying 'drawfings, is arspecification, like letters on the drawings representing like parts. V This invention relates to an internal combustion engine 'or motor and is herein shown as embodied in a motor of the two cycle type;

Theinvention has for its object to provide a motor of the class described, which is economical in fuelconsumption and ofm'jaxi mum eflic-iency, as will be described. I Figure 1 is an elevation of an internal combustion engine or motor. embodyin I this invention. Fig. 2, a vertical .longitu i-nal section of the motorshown in Fig. 1. Fig. 3) a plan with parts in section of the motor. shown in Fig. 2, the section beingtaken on the line 3.3, Fig.8. Fig.4 a detail in section I of the rotary valve shownin Fig 3. Figs. 5, 6,? and 7, details in section to show different positions of the rotary valve. Fig.

8, a vertical'transverse'section of the motor on the line 8 8, Fig, 1'. Fig. 9", an end elevation of the motor shown in Fig.1. Fig. 10, a horizontal section on the line '10'10, Fig. 8. Fig. 1.1, a vertical section of a modification :to be referred to, and Fig. 12,

piston, comprising the working piston 14' a detail in section of the working piston to L be referred to. In the present instance the inventlon 1s shownin an. engine comprising four two cycle motors' a, b, a, (Z, operatively connected with a crankshaft e, and as .all of the motors are of like construction a detailed description of one will suflice to enable the invention to be clearly understood.

Referring to Fig. 8, 10 re resents the ex losionchamber and 12 .t e compressing 5 chamber of a two step or differential-cylinder, containing 'a two step or differential which reciprocates in the chamberdt), and the compressing ist-on 15 which reciprocates in the cham er 12, said pistons being represented'as made in one piece. The pistons 14, 15 as herein shown are made hollow and are in open communication with the crank case 16. upon whichthe cylinders, 12 are mounted, and the piston 14 is closed Patented Mar; 13, 1913:

10 and 12.. i The chamber 10' is provided at its lower end with one or more gas outlet or-exhaust 1 ports 20, which communicate with a gas ou let-or exhaust pipe 21, see Fig. 1, and said chamber is alsoprovided near its lower end but above the level ofthe exhaust port 20,.

1 with one ormore gas inlet, ports'22, which? icoinmunicate with the vcompression."chambr 12, to receiveja'charge of explosive mel diun'r, s'uch as a mixture of air and gasolene, i which "mixture will be hereinafter referred was the 'fresh gas. vThe gas inletport .22' lis located above the exhaust port 20, so that {on thexup str oke of the piston 14, the exf haust-port maybe closed or substantially iclosed before the gas inlet port 22 is opened, ifor,a purpose'as will be described. Y To obtain an economical and efficient" iworking engine or motor, it is desirable that ithe-explosion chamber should be free or sub; lst-antially free fromburnt'or dead gases bejfore the'fresh gas isadmitted therein, and in the present instance, this desirable re-; =sult is obtained by providing for the admission of pure air, into the explosion chamber, jwhen the exhaust port- 20 is opened and the asto scavenger the said explosion chamber iat itsuPPer-end the head 17, see

'withpure air-and drive'out therefrom all.

or substantially all of the burnt or dead gases and leave the explosion chamber filled with pure air. This result is accomplished 1 in the present instance by providing'thepis-' ton 14 below its head with one or more ports 24, see Figs. 8,10, and 12, in its body por-I tion, which are arranged to register with one or more passages or-cavities 25 onthe inner side of the explosion chamber 10, so that air under pressire within the hollow ipiston 14 can passthr'ough the port 24 and ;passage 25 into the explosion chamber 10, at or about-the time the piston14 has reachedthe end of its down'stroke, and has UIICOV'; jered the exhaust port 20,.preferably on the ilastend' of the down stroke and the' beginning of theup stroke of said piston. 5 The passage 25 in the chamber 10 is ar-' ranged below theexhaust port 20, and-is ion fmade longer than the port 24 in the piston }14,-so that on the down stroke of the'piston i141, the port 24 may register with the passage-25 and the latter yet be closed by the upper end oi;the said piston, until the lat- (er has opened the exhaust port 20, whereupon the upper end of the piston 14 on its further downward movement will uncover pass upwardly and then. downwardly to the .by bands or straps 37.

exhaust port 20, as indicated bythe arrows 28, see Fig. 8.

The air forced into the explosion chamber, drives all or substantially all of the burnt or dead gases out of the explosion chamber, and leaves the latter filled with pure air when the exhaust port 20 is closed at the beginning of the up stroke of the piston 14, which previously covered the air passage 25 and shut off the supply of air prior to or about the time the exhaust port 20 is closed. Atmospheric air is admitted int!) the crank case 16 through ports 29 in the chamber 12, which are uncovered on the up stroke of thepisto-n 15. At or about the time the exhaust port 20 is closed, fresh gas under pressure is admitted into the explosion chamber 10 through the inlet or intake, port 22, which is controlled by a valve, preferably a hollow rotary valve, which may be constructed as shown in Figs. 1 to 8, so as to suppl fresh gas fromlthc usual carbureter or other source of supply, into both the compressing chamber and explosion chamber, oras shown in Fig. 11, to control only the supply of fresh gas from the compression chamber into the explosion chamber.

Therotaryvalve shown in Figs. 1 to 8, comprises a 'hollow cylindrical body 30, closed at its ends by heads 31 having journals 32, see Figs. 3 and 4, which are supported by suitable bearings within a cylindrical shell or casing 33, which is represented as composed of a series of sectlons integral with the cylinders, one for each cylinder. The bearings may be of any suitable construction and are herein shown as ball bearings, and each comprise a member 34, see Fig. 3, fast on one of the journals, and a member 35 secured in fixed position within the casing, said members having interposed between them balls 36 or it be rollers.

The sections of the casing 33 may be secured together in anv suitable manner, as

might The hollow valve 30 is rovided with a plurality of ports or openings 38, one for each cylinder, which cooperates with the inlet port 22 in said cylinder,'see Fig. 3, for the passage of gas from within the hollow valve into the cylinder through the inlet port 22 thereof, and the cylindrical body port 40 in the valve casing 33, which is connected by a passage 11 and one or more ports 42 with the compression chamber 12. Each external passage or cavity 39 also cooperates with a port 43 in the casing 33, with which is connected a gas supply pipe .44, which leads from the carbureter or other su' ply of'gas, (not shown) and the externa passage 39 is made wider at one end, so that it may register with the port 43 at the same time the said external passage registers with the port 40 leading to the compressing chamber as represented in Fig. 7.

The rotary valve 30 may be driven from the crank shaft in unison therewithin any suitable manner, as for instance by a link chain 45 passed about sprocket wheels 46, 47 on the crank shaft and valve respectively.

In the operation of the rotary valve, the external passage 39 connects the carburetor or other source of supply with the compressing chamber 12, once for each revolutlon of the crank shaft, so that on the down stroke of the piston 15, fresh gas is drawn from the source of supply through the inlet pipe 44, port 43, external passage 39, port 40, passage 41, and port 42 into the chamber 12. On the up stroke of the piston 15, the fresh gas in the chamber 12 is compressed therein, as the port 40 is closed by a solid portion of the rotary valve, (see Fig. 8); and when the port 38 in the valve registers with the port 40, the interior of the valve 30 is connected with the compressing chamber 12, whereupon the fresh gas at the given or desired pressure flows from the passage 41 through the ports 40, 38 into the interior of the hollow valve, from which it passes out into that explosion chamber 10 of the motor with whose intake port 22 another port 38 of the rotary valve registers. In t e present instance the motor is shown as provided with four differential cylinders with their pistons connected with four cranks of the crank shaft set approximately on the quarter, see Fig. 2, and the position of the ports 38, 39 of the rotary valve cooperating with the four cylinders are represented in Figs. 8, 5, 6 and 7, that is to say, Fig. 8 shows the position of the ports 38,.

- sition represented in Fig. 8, the exhaust portdescribed as follows: Referring to Fig. 8,

exhaust port 20 is wide open and the air port 24 in the piston 14 registers with the passage in the chamber 10. The pistons :14, 15 are at the beginning of their up stroke. "With the pistons and rotary valve in the positions shown in' Fig. 8, air passes from the crank case up through the hollow pistons and through the port 24 and passage 25 into the chamber 10, striking" against the deflector 27, by which it is caused to flow up to the top of the chamber and then down to the exhaust ports 20, driving before it the burnt or dead gases from the previous explosion. The air port 24 and passage 25 are opened a sufiicient length of time to allow enough air to drive out all or substantially all of the burnt gases and leave the chamber 10 filled or substantially filled with-pure air, when the air passage 25 is closed, which is effected slight y in advance of the closing of the exhaust ports by the upwardly moving pistonv 14. While the air is driving out the burnt gases, the gas inlet is closed or substantially closed, so as to avoid waste of gas,'and at or about the time the exhaust port 20 is closed, the rotary valve opens the intake port 22, and fresh gas under pressure of preferably about 5 lbs. is admitted from the hollow rotary valve into the chamber 10, and on the continued upward stroke of the piston 14, said gas is still further compressed until the piston has reached the end of its up stroke-and, is

at the beginning of its down stroke. In the meantime, the fresh gas in the chamber 12 is compressed by the piston 15, until the rotary valve 30 has advanced and brought the port 38 into register with the port 40, whereupon'the fresh gas under forced into the hollow valve. \Vhen the piston 14 is beginning its down stroke, the

compressed charge of fresh gas mixed with pure air is fired in the usual manner by the spark plug or otherwise, and the explosion drives the pistons down into the po- 20 being opened in advance of the air passage 25 on the last portion of the downward stroke of the piston 14. At or about the time the charge is fired, the external passage 39 in the rotary valve, connectsthe gas supply pipe 44 with the chamber 12 and fresh gas is again drawn into the said chamber.

It will be seen, that thecompressin piston of each motor on its up stroke, orces fresh gas at a given or predetermined pressure into the interior of the hollow valve,

1 which acts as a reservoir to hold the fresh gas under pressure and supply the explosion chamber of each motor with fresh gas pressure is I under an initial pressure above the atmos phere, when the gas intake port 22 of each explosion chamber is uncovered.

The initial pressure of the fresh gas ad- .mitted into the; explosion chamber of each motor is greatly increased by the compression or up stroke of the piston in said cham ber, which thereby increases the efficiency of the motor.QFurthermore, the fresh gas is admitted into an explosion chamber which is free or substantially free from only fresh air, consequently the compressed charge in the explosion chamber is exploded under the most favorable conditions, which mot-or. It will be observed that on the down stroke of the piston 15 of larger diameter, a large uantity of fresh air is forced into the cylinder 10, which is of smaller diameter, thereby insuring an abundance of fresh air to completely scavenge the cylinder.

By flushing the explosion chamber with pure air while the gas intake port is closed or substantially closed, all the gases in the explosion chamber after an explosion. are displaced by pure air without loss of fresh gas or explosive medium, which serves to obtain a very economical motor. Furthermore the pure air passing up through the hollow pistons, and into and through the explosion chamber serves to assist in cooling the motor. The pressure to which the fresh gas is raised by the piston 15 can be varied by increasing or decreasing the size or diameterof the chamber 12 and of the portion ofthe piston 14 which extends into the chamber 12. In Fig. 11, is represented an arrangement in which the fresh gas is admitted directly into the chamber 12 through the inlet port 51 with which the carbureter is connected, and employing a hollow rotary valve which need not have the external passages 39 but has only the port 38. In this arrangement dead or burnt gases and contains practically.

also serves to increase the efliciency of the the operation is the same as above described, h

except that the fresh gas is taken directly from the carbureter through the port 51 which is opened and .closed by the piston 15.

In Figs. 1 and 9, I have shown the motor as provided with a system of cooling by air substantially as shown. and described in Letters Patent No. 962437 grantedto the June 28, 1910 and consisting essentiallyo f a substantially air tight casing 543 having a series of bonnets 54, which surround the chambers 10 and through which air ,is drawn by a fan not shown in thefly wheel 55, and whileit may be preferred to use this system of cooling, itis not desired to limit the invention in this respect as the motor- The engine or motor embodying the above invention is-enabled to work equally as well at high speeds-as at lowspeeds, for the reason that the fresh gas "is under pressure before it is" admitted into the explosion chamber, which insures asufiicientquantity of fresh gasbeing admitted to the said chamber even when the intake port is opened for a small space of time when the motor is running at high speeds, and loss of power is avoided by having the explosion chamber free or substantially free from dead or burnt gases. Furthermore the motor is light, durable and inexpensive to maintain on account of the small number of working parts.

laims: I

1. In an internal combustion motor, in combination, a differential cylinder comprising an explosion chamber and a compressing vchamber, said explosion chamber having an exhaust ort, a gas inlet-port locat-ed at a higher level than said exhaust port, and an air passage on its inner surface below said exhaust port, a differential piston comprising a hollow upper piston having a head at its upper end and pro vided with a port in its body portion cooperating with said air passage, and a hol low lower piston attached to said upper piston, a valve casing havinga gas inlet port, and a gas outlet port leading to the compressing chamber, a hollow rotary valve provided with an external passage fwhich cooperates with the as inlet port to connect itwith the port lea ing to the compressing chamber, and having a ort cooperating with the gas inlet port or the explosion chamber to supply fresh gas thereto, and cooperating with the port leading to the compressing chamber to connect the latter with the interior of the hollow valve, for the purpose specified. 2. In an internal combustion motor, in combination, a differential cylinder comprising anyexplosion chamber and a com lpressing.chamber,- said explosion chamber avmg an exhaust ort, a gas inlet port located ata higher evel than said exhaust port, and an. air passage on its inner surface below said exhaust port, a differential piston comprising a hollow upper piston hav with a port its ing' a head at its upper end and provided body portion cooperating with said air passage, and a hollow lower piston. attached to said upper piston, a hollow rotary valve controlling the admission of fresh gas from the compressing chamber into it and from it into the explosion cham- I combination,

pr1s1ng an exploslon chamberand a comf ber, substantially as described.

In an internal combustion motor, in

'a differential cylinder compressing chamber, said explosion chamber being closed at its upper end and having an exhaust portatits lower end, a gas inlet 'said closed at its upper end and having a port in crating with the ports of said valve casing port. at a higher level than said exhaust port and in proximity to the level of said exhaust port, and an air inlet port below said exhaust port, a differential hollow piston in cylinder open at its lower end and its body portion, the piston in the explosion chamber controlling said air' inlet and exhaust ports to permit. the same to be (gen at the same time and allow air to ow through the piston into the explosion cylinder and drive theburnt gases out through the exhaust port, and a rotary valve for closing the said gas inlet port while the exhaust and air inlet ports are open.

4. In an internal combustion motor, .in combination, a differential cylinder comprising an explosionchamber and a com ression chamber of larger diameter, a di erential piston in said chambers, said explosion chamber having an exhaust port, an air inlet port-and-a gas inlet port, and said compression chamber having a gas port, a rotary valve controlling the gas inlet port to the explosion chamber and the gas port to the the gas port for the compression chamber to connect the same with the gas supply on the stroke of the compression piston in one direction and to close said port for the compression chamber for a portion of the stroke of the compression piston ,in the opposite direction to cause the fresh gas to be. compressed in the compression chamber, for the purpose specified. p

5.In an internal combustion motor, in combination, a" differential cylinder comprising-an explosion chamberand a com ression chamber of larger diameter, a di erential piston insaid chambers, said explosion chamber-having an exhaust ort and a gas inlet port controlled by its piston, and said compression chamber having a gas port, a valve casing having a port connected with a supply for fresh gas, and a second port connected with the gas port of the compression chamber to supply fresh gas to the latter, a hollow valve closed at its ends and provided with a body portion having an external passage non-communicating with its interior and having a port communicating with its' interior, said hollow valve being mounted to rotate in said casing and coopto connect the same by means of said external passage, to thereby admit ga's from the supply into the compression chamber on the suction stroke of its piston and to close the second port for said valve casing during a portion of the return stroke of said compression piston, to thereby efi'ect compression of the resh gas in the com ression chamber while the latter is cut ofi rom the-interior of the hollow valve, and thereafter to'connect the port in the body :portion of the hollow valve compression chamber and cooperating with stantially as described.

a some with the second port of the valve casingf'and thereby admit the gas under compression in the compression chamber into ,the hollow 'valve, for the purposespec'ified;

6. In an internal combustion motor, in combination, a diflerential cylinder having.

an explosion chamber and a as compression chamber of larger diameter t an said explosion chamber, thelatter being closed at its upper end and having at its opposite'end an' exhaust p ort, an air inlet port, and. a gas ill-- let port located above the level cr-thegsaid airinlet and exhaust'ports, a hollow d1flerate with said air inlet port andflconnect the the compression chamber and-provided with a portleading to the gas inletport of the explosion'chamber and with-a port leading a to the compression chamber, and a hollow.

valve mounted'to rotate-in said valv'e'casing. ports thereof, sub

and cooperating with the 1 7. In'an internal'.combustion' motor,' in

combination, a plurality; of difierentialcyl- 'inders each having-an explosion chamber provided with a gas inlet, a separate exhaust and a separate ail-inlet, and each having a 1 gas compression "chamber provided with a" gas passage, a hollow differential piston in each of sa1d. cylinders open at'its lower end and having: a port in its body portionwhich 1. 1 cooperates with the air inlet port of the ex- 'plosion chamber to connect the-latter" with the, interior. of. said piston, and a hollow rotary valve cooperating with the gas:v -pas l.

sages of the'compression chambers to open the same and admitfresh gas therein onthe strokeoftheirpistons in'one direction "and .plosion chambers to adm t to close the said passages for a portion of the stroke. of said pistons in" the opposite 'di-. rection to cause the gas in: said compression [chamberslto be compressed therein, and cooperating with said 'g'asinletsior'the excompressed gas from theco'mpression chamber of one cylinder into the explosion chamber of I another cylinder, whereby the explosion'chambers of each differential cylinder is supplied with fresh gas under pressure which i'sffurther compressed by the iston in said-explosion chamber, substantia ly as described.

8. In an internal combustion motor, in

combination, a differential cylinder comprismg an explosion chamber and a compress-- ing chamber, said explosion chamber hav;

ing an exhaust portand an air. inlet port near its lower end, and having a separate gas inlet port, and said compression chamber having. a gas assage, a difierential piston in said cylin er, the piston in said explosion-chamber controlling said exhaust and said air inlet to' permit the explosion cylinder to be substantially clearedaofthe burnt gases and filled with'substantia1ly piire'f'air when saidexhaust and-air inlet ports are closed on one stroke ofsaid piston,

and a hollowlrotary valve for substantially 'closing saidgas inlet port when said ex- I haust port is open and for closing the gas pas's ageof the compression chamber during sion piston,

.75 a portion of the upstroke ofthe compresj 9.. In,. an';internal combustion motor, in

combination, a differential cylinder having an explosion chamber provided with-a gas 'inletpa separate'exhaustand a separate air inlet, and v a. gas compressing chamber having-fa gas 'inle't-and gas outlet, a hollow rotary'valve controlling the admission of .compressed'gas'into said explosion chamber {and the admission of uncompressed gas into gsaid compressing chamber and cooperating with the nae-mo effect compression ofthe gas j in" said compression chamber, and a dif fferential piston in said chambers, the'pis-.' ton in" the explosion chamber controlling said air inlet andexhaust, substantially as described 10. In an internal combustion motor, in

combination, a plurality of cylinders, each.

having an explosion chamber closed atone end} and. providedwith a gas inlet and an "exhaust port near its other end,'and each having a gas compression chamber provided with a gas passage, pistons in said explosion and compression chambers, and a rotary valve 'coiiperating with the gas passages of a the compression chambers to admit fresh gas into said chambers on the stroke of their pistons in one direction and to close said passages and effectv initial compression of 'sa1d gaswithin said compression chambers during a portion of the stroke of their pistons in the opposite direction, and 006 crating with the gas inlets of said exp osion "chambers to admit the initially compressed gas into said explosion chambers, 'to be iurthercompressed therein, for the purpose,

specified.

p 11. In an internal combustidnmotor, in vcombination, a difierential cylinder having an explosion chamber and a gas compressing chamber, of larger diameter than said explosion chamber, a supply of gas connected with the gas compressin chamber, a

'difierential piston in said di erential .cyls

index, 'saidi explosion chamber having an exhaust port, an air inlet port, and a gas in:

letport, a rotaryvalve cooperating with the gas compressing chamber to close the same piston, and'with said gas inlet port to ad.-. :7

mit gas under pressure into said explosion cylinder, after the air inlet and the exhaust a so 12 's and efl'ect the compression therein of fresh gas during a portion of the up stroke of its.

" 'porl liare lieeii substan tielly closed bydhe tial ly es described.

piston in the explosion chamber, substan- 12. In an internal eoi'nbu'stio'n motor; in

combination, a difierential 'o'ylinder having an: ex'plosion'chamber closed at one end and hsiviriga gas inlet port and an exhaustport near its other .end,-arid having, a oompres-.

v sioxi chamber of larger diameter provided '10 with a gas passage, a. differential piston in said chambers, enda hollow rotaryyalve having an external passage non com num eating with its. interior [and cooperating f with thefgas passfigeof, the compression.

chamber, t'o .fadmifi.- fresh gas into. said we;

after 'toiconneot said compression chamber with the. inferior fol the hollowyel f .bustionyohamber to close the seine duringe name J 1321111 an internal oombustion motor, in' loombination, a difierential cylinder an explosion chamber closed at one end and having a gas inlet port andan exhaust port Ynear 1ts -oth er;end,;and heving a conipres- 80 01 chamber-of larger diameter provided with a gas passage, a differential piston in said chambers, end a hollow rotary valve 00- operating withKt hefgas passage of the comp'ortion' of the' return'stroke' of the piston j in the 'com pression" oliambeg; to thereby effect joorppressionof the fre'sh gas in said -celmp1 e1ss1on ehamber aiidthereafterto eonnectfseidf compression chamber with the in having 

